NON-AQUEOUS ELECTROLYTE SECONDARY BATTERY

To provide a non-aqueous electrolyte secondary battery with high capacitance and with improved cycle characteristics.SOLUTION: A non-aqueous electrolyte secondary battery comprises: a positive electrode; a negative electrode; a separator isolating the positive and negative electrodes from each other; and a non-aqueous electrolyte. The positive electrode has a positive electrode current collector, and a positive electrode mixture layer formed on a surface of the positive electrode current collector. The positive electrode mixture layer includes: a first positive electrode mixture layer opposed to the positive electrode current collector; and a second positive electrode mixture layer laminated on a surface of the first positive electrode mixture layer. The first positive electrode mixture layer includes a first positive electrode active material containing Ni and Ca. The second positive electrode mixture layer includes a second positive electrode active material containing Ni and Sr. The percentage content of Ni in the second positive electrode active material is lower than that in the first positive electrode active material.SELECTED DRAWING: Figure 2 【課題】高容量でサイクル特性が向上した非水電解質二次電池を提供する。【解決手段】本開示の一態様である非水電解質二次電池は、正極と、負極と、正極及び負極を相互に隔離するセパレータと、非水電解質とを備え、正極は、正極集電体と、正極集電体の表面に形成された正極合剤層とを有し、正極合剤層は、正極集電体に対向する第１正極合剤層と、第１正極合剤層の表面に積層された第２正極合剤層とを含み、第１正極合剤層は、Ｎｉと、Ｃａとを含有する第１正極活物質を含み、第２正極合剤層は、Ｎｉと、Ｓｒとを含有する第２正極活物質を含み、第２正極活物質におけるＮｉの含有率は、第１正極活物質におけるＮｉの含有率よりも低い。【選択図】図２